Surgical Therapy of Parkinson\u27s Disease

The history of surgical treatment of Parkinson\u27s disease (PD) covers more than 100 years. It started from lesional approach and evolved to the final deep brain stimulation (DBS) only in the 1990s. The aim of this treatment was to reduce clinical manifestation of PD and drug intake by acting directly on the altered motor pathways. The typical targets are represented by ventralis intermedius thalamic nucleus (VIM), internal globus pallidus nucleus (GPi), and subthalamic nucleus (STN) with more recent extension on other anatomical structures as pedunculopontine nucleus (PPN). Patients are selected according to CAPSIT protocol and undergo DBS when medical treatment has failed to effectively control the symptoms. Clinical benefits are represented by the reduction of “off” time and “on” time with dyskinesia. However, even DBS treatment is characterized by complications and side effects, as intracerebral hemorrhages, infections, ischemia, and seizures. The recent introduction of neuronavigation systems and the amelioration in neuroradiological imaging quality simplified preoperative DBS planning and consequently reduced surgical‐related problem

Scaling violations: Connections between elastic and inelastic hadron scattering in a geometrical approach

Starting from a short range expansion of the inelastic overlap function, capable of describing quite well the elastic pp and $\bar{p}p$ scattering data, we obtain extensions to the inelastic channel, through unitarity and an impact parameter approach. Based on geometrical arguments we infer some characteristics of the elementary hadronic process and this allows an excellent description of the inclusive multiplicity distributions in $pp$ and $\bar{p}p$ collisions. With this approach we quantitatively correlate the violations of both geometrical and KNO scaling in an analytical way. The physical picture from both channels is that the geometrical evolution of the hadronic constituents is principally reponsible for the energy dependence of the physical quantities rather than the dynamical (elementary) interaction itself.Comment: 16 pages, aps-revtex, 11 figure

Inhibition of PI3K Signalling Selectively Affects Medulloblastoma Cancer Stem Cells

Medulloblastoma is the most common malignant brain tumor of childhood. Although survival has slowly increased in the past years, the prognosis of these patients remains unfavourable. In this context, it has been recently shown that the intracellular signaling pathways activated during embryonic cerebellar development are deregulated in MDB. One of the most important is PI3K/AKT/mTOR, implicated in cell proliferation, survival, growth, and protein synthesis. Moreover, a fraction of MDB cells has been shown to posses stemlike features, to express typical neuronal precursor markers (Nestin and CD133), and to be maintained by the hypoxic cerebellar microenvironment. This subpopulation of MDB cells is considered to be responsible for treatment resistance and recurrence. In this study, we evaluated the effects of PI3K/AKT pathway inhibition on primary cultures of MDB and particularly on the cancer stem cell (CSC) population (CD133(+)). PI3K inhibition was able to counteract MDB cell growth and to promote differentiation of stemlike MDB cells. Moreover, PI3K/AKT pathway suppression induced dramatic cell death through activation of the mitochondrial proapoptotic cascade. Finally, analysis on the stem cells fraction revealed that the MDB CSC population is more sensitive to PI3K targeting compared to the whole cancerous population and its nonstem cell counterpart

Radiological outcomes for endovascular treatment of posterior communicating artery aneurysms: a retrospective multicenter study of the occlusion rate

Although several innovations in techniques and implantable devices were reported over the last decades, a consensus on the best endovascular treatment for intracranial aneurysms originating from the posterior communicating artery is still missing. This work investigates radiological outcomes of different endovascular techniques for posterior communicating artery aneurysms treatment in a retrospective multi-centric cohort. We included patients endovascularly treated for posterior communicating artery aneurysms from 2015 through 2020 in six tertiary referral hospitals. We evaluated the relationship between patients and aneurysms characteristics, baseline neurological status, radiological outcomes, and the different endovascular techniques. Overall, 250 patients were included in this study. Simple coiling was the most frequent treatment in 171 patients (68%), followed by flow-diverter stenting in 32 cases (13%). Complete occlusion was reported in 163 patients (65%), near-complete occlusion in 43 (17%), and incomplete occlusion in 44 (18%). Radiological follow-up was available for 247 (98%) patients. The occlusion rate was stable in 149 (60%), improved in 49 (19%), and worsened in 51 (21%). No significant difference in exclusion rate was seen between ruptured and unruptured aneurysms at the last follow-up (p = 0.4). Posterior communicating artery thrombosis was reported in 25 patients (9%), transient ischemic attack in 6 (2%), and in 38 patients (15%), subsequent procedures were needed due to incomplete occlusion or reperfusion. Endovascular strategies for posterior communicating artery aneurysms represent effective and relatively safe treatments. Simple coiling provides a higher immediate occlusion rate, although recanalization has been frequently reported, conversely, flow-diversion devices provide good long-term radiological outcomes

The impact of COVID-19 pandemic on surgical neuro-oncology: A survey from the Italian society of neurosurgery (SINch)

Background: The COVID-19 pandemic and its impact on hospitals' activity and organization has imposed a vast change in standard neurosurgical oncology practice to accommodate for shifting resources. Aims: This investigation aims to analyse the nationwide capability in reorganizing the surgical neuro-oncological activity during the COVID-19 pandemic to evaluate whether COVID-19-pandemic influenced the surgical management in these patients. Method: A web-based dataset model organized by the Italian Neurosurgical Society (SINCh) was sent to all the Italian neurosurgical departments in May 2021, requesting to report the types and numbers of surgical procedures performed in the pre-pandemic period (from March 9th 2019 to March 9th 2020) compared to the pandemic period (from March 10th 2020 to March 10th 2021). Results: This multicentre investigation included the surgical activity of 35 Italian Neurosurgical Departments in a pre-pandemic year versus a pandemic year. During the COVID period, 699 fewer neuro-oncological patients were operated on than in the pre-COVID period. We noted a slight increase in urgency and a more severe decrease in elective and benign pathology. None of these differences was statistically significant. Surgically treated patients who tested positive for SARS-CoV-2 were 36, of which 11 died. Death was found to be COVID-related only in 2 cases. Conclusion: The reorganization of the Italian Neurosurgical Departments was able to guarantee a redistribution of the CNS tumors during the inter-pandemic periods, demonstrating that patients even in the pandemic era could be treated without compromising the efficacy and safety of the surgical procedure